1. Field of the Invention
The present invention relates to an improved device for manufacturing sandals. The device includes a last covered by the strap of the sandal. The last provides the upper limitation of a mold cavity of an injection molding tool for molding a sole onto the shaft. The cavity is formed by lateral parts of the mold and, if need be, a bottom last. The upper edges of the lateral parts of the mold with the complementary contour of the last, form a sealing zone for the cavity of the mold.
Such a device allows multi-layered, multicolored soles made of plastic and/or rubber to be directly molded onto the shaft put into the last, with one or several layers, in one or more colors. The top part of the sandal, formed by the straps, is stitched to an insole consisting of fabric or leather.
2. The Prior Art
The seal between the molded lateral parts and the shaft generally poses no problems with normal shoe shafts. However, with sandals, the area between the straps of the sandal are critical zones because the straps have a thickness ranging from 1.5 to 2.5 mm. Without additional sealing measures, sole material would exit from the mold cavity through the slits remaining between the edges of the molded side parts and the last.
Therefore, the open areas between the straps were bridged heretofore by inserting strips of textile or leather materials.
In addition to an increase in material consumption, this step has the drawback that such intermediate layers have to be inserted with each shaft by an additional work step in the areas between the straps. Following injection-molding of the sole, such intermediate layers have to be removed again, which constitutes a significant expenditure of time. The intermediate layers have to be exactly cut to fit, and provision has to be made for different measures for each sandal model of each size. This requires additional storage space to keep intermediate layers having all sorts of different dimensional sizes.